Bud Abbott
Cuthbert Greenway / Dr. Ralph Greenway
Lou Costello
Horatio Prim
Marjorie Reynolds
Melody Allen
Binnie Barnes
Mildred Dean
John Shelton
Sheldon Gage
Gale Sondergaard
Emily
Lynn Baggett
June Prescott
Jess Barker
Thomas Danbury
Ann Gillis
Nora O'Leary
Donald MacBride
Lt. Mason
William Hall
Sgt. Conners
Robert Barrat
Maj. Putnam
Rex Lease
Sgt. Makepeace
Kirk Alyn
Dandy at Party (uncredited)
Harry Brown
Second Sergeant (uncredited)
George M. Carleton
Museum Guard (uncredited)
Wheaton Chambers
Bill - Museum Guard (uncredited)
James Conaty
Party Guest (uncredited)
John Crawford
Dandy at Party (uncredited)
Vernon Downing
Leigh - Traitor (uncredited)
Marjorie Eaton
Bessie - Danbury's Maid (uncredited)
Myron Healey
Dandy at Party (uncredited)
Boyd Irwin
Cranwell - Traitor (uncredited)
Selmer Jackson
Mr. Dibbs - Museum Curator (uncredited)
William H. O'Brien
Danbury Servant (uncredited)
Scott Thomson
Dandy at Party (uncredited)
Harry Woolman
Motorcycle Rider (uncredited)